saltwater fish cannot survive in fresh water, will explode due to osmosis
less forest, less rain (as less evapotranspiration)
jetty is connected with castle-like thing through underground pipes
Water from reservoir flows into inlet through pipe to pump to Bradell (use of pressure) –> purification –> house
Pink buoys and flexible hoses carry air – pump air into water to keep the water alive for plants, fishes and crustaceans – ecosystem
Radio towers at Bukit Timah
Water at Bukit Timah flows to Upper Peirce Reservoir then to Lower Peirce Reservoir
Ang Mo Kio and Bishan will be flooded immediately if the dam is damaged
The place used to be all forest with complex network of streams
Drains lead to Kallang River
Straight feature of dam is highly important
Boats are used by reservoir management staff to create currents to push rubbish from centre to side –> create water movement –> oxygenate water
Left of dam: oil palm plantation. Back of dam (hilly area): rubber tree plantation.
–> thick secondary forest, mature
overflow gate: for 'excess' water to flow out into monsoon drain to sea
scum: mixture of chemicals (leached from golf course) and algae – at first white –> brown, foamy as anaerobic decomposition of animals releases chemicals
impact of golf course: fertilisers for plants go into water –> algae population increase –> short lived –> mass dying of algae –> bacteria deplete oxygen supply –> fish die –> fish decompose –> water turns foul <EUTROPHICATION>
island bridge – granite rounded steps down, passages, to Kallang River. Rapid water is split by island –> water from both sides meet in the middle, clash against each other –> force of water decreased, slower speed –> safeguard banks
mapping structures (bluish-green) are lined in a perfectly straight line. surveyors use precision instrument to check straightness as any misalignment would be the first sign/warning: there is ground movement due to water pressure
rocks at the fishing area are there to mitigate soil erosion
streams have native fishes
aNiMaLs AnD pLaNtS fOuNd ThErE:
koel: starts chirping at 5am; high-pitched, varying tone (low–>high)
kingfisher: trill, up-down pitch
white-bellied sea eagle: good eyesight; uses talons to grab fish out of water, only flaps when at low altitude, at high altitude hot air rises to push wings
snakehead fish: good to make soup after surgery
manila plant: bright red fruits attract honey bees
taiping tree: orange, sweet smelling flowers attract a lot of birds and insects; native tree of Malaysia; planted as horticulture fruit
iron wood tree: from India (not native); bark peels off, patches of orange (algae), brownish yellow, brown and white (when peeled)
fig: waringin tree
albizia: looks like raintree
tembusu: produces creamy white flowers which turn yellow overnight, orange/red berries attract monkeys, squirrels and bats
pulai: good tree from primary forest
leban: needs a lot/intense light to grow; used as wood to make daily tools in the past; found at forest edge; attracts butterflies
tapioca: shrub
cabbage tree: light green; often found in isolated islands; can live in dry environments
long tailed macaque: cuddle, groom , jump around. males have pointy fur in the mid top of their heads
pitta: blue migratory bird
buffy fish owl
cicadas: make sounds alternating about the pitches F-sharp and G
These plants are signs that the forest has reached a mature state. Birds bring seeds in (e.g. from Bukit Timah which is a primary forest)
Maturity of secondary forest depends on: size of trees, type of trees. There are primary elements within secondary forest.
Secondary forests are shorter, have lower shrubs, plants are more spaced apart, more light enters, fewer species
Proximity to primary forest is important for secondary forest maturation
WhY mUsT pRoTeCt ThE fOrEsTs?
Vegetation cover helps to filter water as water percolates through trees and soil and travels underground into reservoir instead of simply surface runoff
forests are like sponges which slowly release water
They produce oxygen and absorb carbon dioxide
carbon sinking –> mitigate global warming –> capture carbon and lock it in the ground
habitat, ecosystem for living things
They clear the air – particles get trapped on surface –> rain –> washed away and locked in ground
rich medicinal value
indigenous people, their livelihood, culture and history
aNiMaLs AnD pLaNtS fOuNd ThErE:
WhY mUsT pRoTeCt ThE fOrEsTs?